Intercommunication devices



M 1956 (a. SCHOENEBERG INTERCOMMUNICATION DEVICES 2 Sheets-Sheet 1 Original Filed Aug. 2. 1954 ATTORNEY Sept. 18,

1956 c. SCHOENEBERG INTERCOMMUNICATION DEVICES Original Filed Aug. 2, 1954 2 Sheets-Sheet 2 Cami ATTORNEY United States Patent 2,7 63,7 19 MERCOMMUNICATION DEVICES Carl Schoeneberg, St. Petersburg, Fla., assignor to Jay V. Zimmerman Company, St. Louis, Mo., a corporation of Missouri Original application August 2, 1954, Serial No. 447,034. Divided and this application April 4, 1955, Serial No. 499,048

11 Claims. (Cl. 179-1) This invention relates in general to certain new and useful improvements in intercommunication devices and, more particularly, to a simplified self-contained intercommunication unit of the telephonic type, and is a division of my copending application Serial No. 447,034, filed August 2, 1954.

At the present time, intercornmunication systems consist of a first unit or station which contains either a conventional loud speaker or earphone electrically connected through some type of amplifier circuit and conductor to a microphone mounted in a second or remote station with which communication is to be established. Ordinarily, the remote station also has a loud speaker or earphone similarly connected to a microphone in the first station. Frequently, only one station is provided with an amplifier circuit designed for interchangeable use in either transmitting or receiving a signal under the control of a so-called talk-listen switch, and such devices, because of economy, are widely in use. However, even the simplest amplifier circuit necessitates the use of vacuum tubes or transistors and other expensive components and is, therefore, relatively costly. Furthermore, such devices are, at best, fragile and often require servicmg.

It is, therefore, the primary object of the present invention to provide an intercommunication device which is compact, simple and economical in construction.

It is another object of the present invention to provide a device of the type stated having a unique transducer or voice-responsive unit capable of alternative use either as a microphone or a loud speaker.

It is a further object of the present invention to provide a device of the type stated which will operate efficiently over reasonable distances of the order of several hundred feet with the use of simple dry batteries or other relatively inexpensive low voltage power source and without amplification means or similar electronic components.

With the above and other objects in view, my invention resides in the novel features of form, construction, arrangement, and combination of parts presently described and pointed out in the claims.

In the accompanying drawings (two sheets) Figure 1 is a perspective view of an intercommunication unit constructed in accordance with and embodying the present invention;

Figure 2 is a side elevational view of the intercommunication device shown in Figure 1;

Fig. 3 is a vertical sectional view taken along line 33 of Figure 2;

Figure 4 is a vertical sectional view taken along line 4-4 of Figure 1;

Figure 5 is a fragmentary sectional view taken along line 55 of Figure 2; and

Figure 6 is a schematic wiring diagram illustrating the circuit forming a part of the present invention.

Referring now in more detail and by reference characters to the drawings, which illustrate a preferred embodiment of the present invention, A generally desig nates an intercommunication unit comprising an outer housing or shell 1 preferably molded from a synthetic Patented Sept. 18, 1956 ice resin such as Bakelite or polystyrene and integrally including an open-bottomed rectilinear base section 2 surmounted by an upwardly projecting prismatically shaped top section 3 having oblique front and rear walls 4, 5, transversely connected by side walls 6, 7, and a top wall 8. The front wall is cut out to provide a grill-work 9 through which sound may freely travel as is customary in such devices. The base section 2 is substantially larger from front to rear than the top section 3 and juts forwardly therefrom in the formation of an upwardly presented ledge 10, which is provided with. vertical tubular sleeves 11, 12, for respectively supporting shiftable pushrods 13, 14, having switch buttons 15, 16, on their upper ends. At their lower ends, the push-rods 13, 14, project into the interior of the base section 2 and respectively bear against the opposite ends of a spring-leaf contactor or switch blade 17 which is secured approximately at its center upon a boss 18 formed on the under face of the ledge 10 by means of a screw 19 or other similar fastening means. One end of the switch blade 17 overlies two separate contact elements 20, 21, rigidly mounted in the base section 2 and, similarly, the other end of the switch blade 17 overlies a single contact element 22 also rigidly mounted in the base section 2, all as best seen in Figure 5. It should be noted in this connection that the push-rods 13, 14, are provided with stop-pins 23 and are biased upwardly by the switch blade 17 so that normally the stop-pins 23 abut against the under faces of the sleeves 11, 12. The stop-pins 23 also prevent unauthorized or accidental removal of the push-rods 13, 14.

Provided for disposition within the top section 3 is a transducer or voice-responsive element B comprising a cone-shape metal frame or chassis 24 having ventilation apertures 25 and a rim 26 provided with perforated lugs 27 by which it is firmly attached to the inner face of the front wall 4 directly behind the grill-work 9. Disposed symmetrically within the chassis 24 in inwardly spaced relation thereto is a voice-sensitive cone 28 formed of paper or similar material capable of vibrating sensitively and vigorously under mechanical forces such as sound waves and the like.

The cone 28 is provided at its outer or large end with a flat peripheral flange 29 which is rigidly secured to the chassis 24. At its interior or small end, the cone 23 is provided with an aperture 30 and around such aperture is glued to a corrugated buckram diaphragm 31, which extends concentrically therearound, and at its outer peripheral margin is adhesively secured to the chassis 24, which is, in turn, provided with an inwardly extending annular flange 32 having a concentric aperture 33. Riveted or otherwise rigidly mounted upon the flange 32 and extending coaxially to the rear thereof is a rectangular magnetic yoke 34 having an aperture 35 in registration with the aperture 33 of the chassis flange 32. Rigidly mounted centrally of the rear portion of the yoke 34 and extending forwardly and concentrically through the apertures 33, 35, is a rod-shaped permanent magnet M preferably formed of Alnico or high permeability material and being substantially smaller in diameter than the apertures 33, 35, so as to provide an annular space s therebetween. The magnet M is housed within a tubular sheet metal shell 36, the front end of which is flared conically outwardly, as at 37, to enclose the apertures 33, 35.

Adhesively or otherwise tightly secured upon the forward face of the cone 28 in concentric and closureforming relation across the aperture 30, is a light metal disk 38, which is, in turn, similarly provided upon its forward face with a concentric resilient insulating ring 39 and a metallic disk 40 arranged to provide an enclosed space s, which is packed with carbon granules. The disks 38 and 40 are preferably gold plated to afford good electrical contact with the carbon granules and are also provided with electrical lead wires 41, 42, respectively.

Also adhesively secured to the diaphragm 31 and disposed in concentric relation to the aperture 30 is a lightweight paper tube 43 which extends freely through the space s and is externally provided with a fine wire winding or voice-coil 44. As will be seen by reference to Figure 4, the tube 43 and voice-coil 44 do not touch the surfaces of the magnet M or the metal edges around the apertures 33, 35, and it will also be noted that the forward flat end of the magnet M is located rearwardly of the aperture 30, but the voice-coil 44 is located so that it is almost entirely around the forward portion of the magnet M and is entirely within the magnetic field thereof. The voice-coil 44 is also provided with two flexible wire leads or conductors 45, 46, respectively, by which it is connected into the circuit as will be presently more fully discussed.

Removably secured in and extending across the open bottom of the housing or shell 1 is a bent bottom plane 47 comprising a forward lower portion 48 and a rearward upper portion 49 integrally connected by an intermediate or oblique section 50. The rearward upper portion is located sufiiciently above the plane of the bottom of the housing or shell 1 to provide an open-bottomed chamber or compartment c for housing conventional dry cells or batteries 51, which are held in place by means of spring clips 52, 53, and are conventionally provided with lead wires or electrical connections 54, 55. Mounted upon the upwardly presented interior face of the forward lower portion 48 is a vibrator V of substantially conventional design and including an electro-magnet 56 having wire conductors or leads 57, 58, and an armature 59 having make-and-break contacts 60, 61.

The above described components are electrically connected together in a circuit as shown in the Wiring diagram, Figure 6. As will be seen by reference to Figure 6, the intercommunication system consists of two units A, A, which are connected by suitable lengths of conventional electrical connector wire, as indicated by the dot-dash lines. It will, of course, be evident that these connector wires can take the form of a single threewire conductor if desired.

In use, two identical units A, A, may be placed in two different localities separated by several hundred feet more or less at option of user and electrically connected as indicated in Figure 6. For purposes of clarity, it is preferable to refer to unit A as station I and unit A as station II. If, for example, the user at station I desires to communicate with station II, he merely presses the switch button which closes the circuit between the battery 51 and vibrator V, energizes the latter, and generates a high-frequency transient which travels to the voice-coil 44 at station II and produces therein an audible signal notifying the user at station II that he is being called by the user of station I, and can indicate his availability to receive a message by pressing down the switch button 15 of his own unit. The vibrator V at station I will, in addition to generating a transient, also emit a buzzing sound at station I which results from its mechanical operation and this buzzing sound is audible to the user of station II. However, the transient thus generated does not affect the voice-coil at Station 1. Consequently, when the user at station II presses down the switch button 15, energizing the vibrator V in his own unit, the transient generated thereby will be imposed upon the voice-coil of the unit at station I, causing it to emit an audible signal. Thereupon, a two-way conversation of the talk-and-listen type can be carried out by pressing down the switch buttons 16 for talking and releasing them for listening. In other words, when the switch button 16 at station I is pressed down and the switch button 16 at station II is released, station I can talk to station II. Conversely, by releasing the switch button 16 at station I and pressing down the switch button at station II, station II can talk to station I. When the intercommunication system is not being used, both switch buttons 15, 16 in each unit, will be released and there will be no drain in the batteries 51 in either unit A or unit A.

It should be understood that changes and modifications in the form, construction, arrangement, and combination of the several parts of the intercommunication devices may be made and substituted for those herein shown and described without departing from the nature and principle of my invention.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. An intercommunication unit comprising a housing having an open grill and an interior compartment behind the grill, a vibratory member mechanically responsive to sound waves, said vibratory member being mounted within the compartment directly behind the grill, a voice coil operatively associated with the vibratory member and having two terminals, a carbon-granule microphone having a diaphragm secured to and actuated by the vibratory member and a terminal member located outwardly from the diaphragm, a power source having two terminals, a magnetic vibrator having two armature terminals and two magnet-winding terminals, one armature terminal being connected to one terminal of the power source, the other terminal of the power source being connected in common to one terminal of the voice coil and to the diaphragm, and switch means having first, second, and third contacts and contactor means normally out of contact therewith, said contactor means being adapted for optionally contacting the first contact alone and contacting the second and third contacts simultaneously, said first contact being connected to the terminal member of the microphone, said second contact being connected to the common connection between the power source, voice coil, and diaphragm, said third contact being connected to the one magnet-winding terminal of the vibrator, the other magnet-winding terminal of the vibrator being connected to the other armature terminal.

2. An intercommunication unit comprising a housing having an open grill and an interior compartment behind the grill, a vibratory member mechanically responsive to sound waves, said vibratory member being mounted within the compartment directly behind the grill, a voice coil operatively associated with the vibratory member and having two terminals, a carbon-granule microphone having a diaphragm secured to and actuated by the vibratory member and a terminal member located outwardly from the diaphragm, a power source having two terminals, a magnetic vibrator having two armature terminals and two magnet-Winding terminals, one armature terminal being connected to one terminal of the power source, the other terminal of the power source being connected in common to one terminal of the voice coil and to the diaphragm, switch means having first, second, and third contacts and contactor means normally out of contact therewith, said contactor means being adapted for optionally contacting the first contact alone and contacting the second and third contacts simultaneously, said first contact being connected to the terminal member of the microphone, said second contact being connected to the common connection between the power source, voice coil, and diaphragm, said third contact being connected to the one magnet-winding terminal of the vibrator, the other magnet-Winding terminal of the vibrator being connected to the other armature terminal, and three connector elements adapted for connection to conductors leading to a matching intercommunication unit, one of the connector elements being connected to the common connection between the armature terminal and the magnet-coil winding, another connector element being connected to the other terminal of the voice coil, and .the other connector element being connected to the contactor means.

3.- An intercommunication system including two identical intercommunication units each comprising a housing having an open grill and an interior compartment behind the grill, a vibratory member mechanically responsive to sound waves, said vibratory member being mounted within the compartment directly behind the grill, a voice coil operatively associated with the vibratory member and having two terminals, a carbon-granule microphone having a diaphragm secured to and actuated by the vibratory member and a terminal member located outwardly from the diaphragm, a power source having two terminals, a magnetic vibrator having two armature terminals and two magnet-winding terminals, one armature terminal being connected to one terminal of the power source, the other terminal of the power source being connected in common to one terminal of the voice coil and to the diaphragm, switch means having first, second, and third contacts and contactor means normally out of contact therewith, said contactor means being adapted for optionally contacting the first contact alone and contacting the second and third contacts simultaneously, said first contact being connected to the terminal member of the microphone, said second contact being connected to the common connection between the power source, voice coil, and diaphragm, said third contact being connected to the one magnet-winding terminal of the vibrator, the other magnet-winding terminal of the vibrator being connected to the other armature terminal, and first, second, and third connector elements, the first connector element being connected to the common connection between the armature terminal and the magnet-coil terminal, the second connector element being connected to the other terminal of the voice coil, and the third connector element being connected to the contactor, said unit being electrically connected by three conductors so that the first connector element of each unit is connected to the third connector element of the other unit and the second connector elements of both units are connected to each other.

4. An intercommunication unit comprising a housing having an open grill and an interior compartment behind the grill, a vibratory member mechanically responsive to sound waves, said vibratory member being mounted within the compartment directly behind the grill, a voice coil operatively associated with the vibratory member and having two terminals, a carbon-granule microphone having a diaphragm secured to and actuated by the vibratory member and a terminal member located outwardly from the diaphragm, a power source having two terminals, a magnetic vibrator having two armature terminals and two magnet-winding terminals, one armature terminal being connected to one terminal of the power source, the other terminal of the power source being connected in common to one terminal of the voice coil and to the diaphragm, switch means having first, second, and third contacts and contactor means normally out of contact therewith, said contactor means being adapted for optionally contacting the first contact alone and contacting the second and third contacts simultaneously, said first contact being connected to the terminal member of the microphone, said second contact being connected to the common connection between the power source, voice coil, and diaphragm, said third contact being connected to the one magnetwinding terminal of the vibrator, the other magnet-winding terminal of the vibrator being connected to the other armature terminal, and a pair of push-buttons operatively mounted in the housing for respectively actuating the contactor to engage the first contact or the second and third contacts.

5. An intercommunication unit comprising a housing having an open grill and an interior compartment behind the grill, a vibratory member mechanically responsive to sound waves, said vibratory member being mounted within the compartment directly behind the grill, a voice coil operatively associated with the vibratory member and having two terminals, a carbon-granule microphone hav ing a diaphragm secured to and actuated by the vibratory member and a terminal member located outwardly from the diaphragm, a power source having two terminals, a magnetic vibrator having two armature terminals and two magnet-winding terminals, one armature terminal being connected to one terminal of the power source, the other terminal of the power source being connected in common to one terminal of the voice coil and to the diaphragm, and switch means having first, second, and third contacts and a contactor blade normally out of contact therewith, said contactor blade being mechanically fastened intermediate its ends and being free at its opposite ends so that one end thereof may optionally engage the first contact alone and the other end may optionally engage the second and third contacts simultaneously, said first con tact being connected to the terminal member of the microphone, said second contact being connected to the common connection between the power source, voice coil, and diaphragm, said third contact being connected to the one magnet-Winding terminal of the vibrator, the other magnet-winding terminal of the vibrator being connected to the other armature terminal.

6. An intercommunication unit comprising a housing having an open grill and an interior compartment behind the grill, a vibratory member mechanically responsive to sound waves, said vibratory member being mounted within the compartment directly behind the grill, a voice coil operatively associated with the vibratory member and having two terminals, a carbon-granule microphone having a diaphragm secured to and actuated by the vibratory member and a terminal member located outwardly from the diaphragm, a power source having two terminals, a magnetic vibrator having two armature terminals and two magnet-winding terminals, one armature terminal being connected to one terminal of the power source, the other terminal of the power source being connected in common to one terminal of the voice coil and to the diaphragm, switch means having first, second, and third contacts and a contactor blade normally out of contact therewith, said contactor blade being mechanically fastened intermediate its ends and being free at its opposite ends so that one end thereof may optionally engage the first contact alone and the other end may optionally engage the second and third contacts simultaneously, said first contact being connected to the terminal member of the microphone, said second contact being connected to the common. connection between the power source, voice coil, and diaphragm, said third contact being connected to the one magnet-winding terminal of the vibrator, the other magnet-winding terminal of the vibrator being connected to the other armature terminal, and a pair of push-buttons operatively mounted in the housing for respectively engaging and actuating the ends of the contactor blade.

7. An intercommunication unit comprising a housing having an open grill and an interior compartment behind the grill, a vibratory member mechanically responsive to sound waves, said vibratory member being mounted within the compartment directly behind the grill, a voice coil operatively associated with the vibratory memher and having two terminals, a carbon-granule microphone having a diaphragm secured to and actuated by the vibratory member and a terminal member located outwardly from the diaphragm, said terminal member having substantially greater mass than the diaphragm so as to be relatively insensitive to mechanical motion in relation to the diaphragm, a power source having two terminals, a magnetic vibrator having two armature terminals and two magnet-winding terminals, one armature terminal being connected to one terminal of the power source, the other terminal of the power source being connected in common to one terminal of the voice coil and to the diaphragm, and switch means having first,

second, and third contacts and contactor means normally out of contact therewith, said contactor means being adapted for optionally contacting the first contact alone and contacting the second and third contacts simultaneously, said first contact being connected to the terminal member of the microphone, said second contact being connected to the common connection between the power source, voice coil, and diaphragm, said third con-tact being connected to the one magnet-winding terminal of the vibrator, the other magnet-winding terminal of the vibrator being connected to the other armature terminal.

8. An intercommuncation unit comprising a housing having an open grill and an interior compartment behind the grill, a vibratory member mechanically responsive to sound waves, said vibratory member being mounted within the compartment directly behind the grill, a voice coil operatively associated with the vibratory member and having two terminals, a carbon-granule microphone having a diaphragm secured to and actuated by the vibratory member and a terminal member located outwardly from the diaphragm, said terminal member being relatively immobile with respect to the diaphragm, a power source having two terminals, a magnetic vibrator having two armature terminals and two magnetwinding terminals, one armature terminal being connected to one terminal of the power source, the other terminal of the power source being connected in common to one terminal of the voice coil and to the diaphragm, and switch means having first, second, and third contacts and contactor means normally out of contact therewith, said contactor means being adapted for optionally contacting the first contact alone and contacting the second and third contacts simultaneously, said first contact being con nected to the terminal member of the microphone, said second contact being connected to the common connection between the power source, voice coil, and diaphragm, said third contact being connected to the one magnet-Winding terminal of the vibrator, the other magnetwinding terminal of the vibrator being connected to the other armature terminal.

9. An intercommunication unit comprising a housing having an open grill and an interior compartment behind the grill, a vibratory member mechanically responsive to sound Waves, said vibratory member being mounted within the compartment directly behind the grill, a voice coil operatively associated with the vibratory member and having two terminals, a voice transmitter having a vibratory element mechanically secured to and actuated by the vibratory member and a terminal member located outwardly from the vibratory element, a power source having two terminals, a magnetic vibrator having two armature terminals and two magnetwinding terminals, one armature terminal being connected to one terminal of the power source, the other terminal of the power source being electrically connected in common to one terminal of the voice coil and to the vibratory element of the voice transmitter, switch means having first, second, and third contacts and contactor means normally out of contact therewith, said contactor means being adapted for optionally contacting the first contact alone and contacting the second and third contacts simultaneously, said first contact being connected to the terminal member of the voice transmitter, said second contact being connected to the common connection between the power source, voice coil, and the vibratory element of the voice transmitter, said third contact being connected to the one magnet-winding terminal of the vibrator, the other magnet-winding terminal of the vibrator being connected to the other armature terminal, and three connector elements adapted for connection to conductors leading to a matching intercommunication unit, one of the connector elements being connected to the common connection between the armature terminal and the magnet-coil winding, another connector element being connected to the other terminal 8 of the voice coil, and the other connector element being connected to the contactor means.

10. A talk-listen instrument of the switch-over type comprising an open framework, a vibratory cone suspended within said framework with its apex presented in a rearward direction and its base presented in a forward direction, said apex having an aperture therein, a diaphragm operatively positioned across said aperture, a voice coil assembly mounted on said framework rearwardly of said apex and being operatively connected to said cone, a microphone secured to said diaphragm, said microphone comprising a conductive disk spaced forwardly of said diaphragm, said disk having a substantially greater mass than the diaphragm so as to be relatively insensitive to mechanical motion in relation to said diaphragm, a power source having two terminals, a magnetic vibrator having two armature terminals and two magnet-winding ter minals, one armature terminal being connected to one terminal of the power source, the other terminal of the power source being connected in common to one terminal of the voice coil and to the diaphragm, and switch means having first, second, and third contacts and contactor means normally out of contact therewith, said contactor means being adapted for optionally contacting the first contact alone and contacting the second and third contacts simultaneously, said first contact being connected to the conductive disk of the microphone, said second contact being connected to the common connection between the power source, voice coil, and diaphragm, said third contact being connected to the one magnet-winding terminal of the vibrator, the other magnet-winding terminal of the vibrator being connected to the other armature terminal.

11. A talk-listen instrument of the switch-over type comprising an open framework, a vibratory cone suspended within said framework with its apex presented in a rearward direction and its base presented in a forward direction, said apex having an aperture therein, a diaphragm operatively positioned across said aperture, a voice coil assembly mounted on said framework rearwardly of said apex and being operatively connected to said cone, a microphone secured to said diaphragm, said microphone comprising an insulating member secured at one end to said diaphragm, a conductive disk spaced forwardly of said diaphragm and secured to the other end of said insulating member, said disk having a substantially greater mass than the diaphragm so as to be relatively insensitive to mechanical motion in relation to said diaphragm, a power source having two terminals, a magnetic vibrator having two armature terminals and two magnetwinding terminals, one armature terminal being connected to one terminal of the power source, the other terminal of the power source being connected in common to one terminal of the voice coil and to the diaphragm, and switch means having first, second, and third contacts and contactor means normally out of contact therewith, said contactor means being adapted for optionally contacting the first contact alone and contacting the second and third contacts simultaneously, said first contact being connected to the conductive disk of the microphone, said second contact being connected to the common connection between the power source, voice coil, and diaphragm, said third contact being connected to the one magnet-winding terminal of the vibrator, the other magnet-winding terminal of the vibrator being connected to the other armature terminal.

References Cited in the file of this patent UNITED STATES PATENTS 

